inotifywait(1)                        General Commands Manual                        inotifywait(1)

NAME
       inotifywait - wait for changes to files using inotify

SYNOPSIS
       inotifywait  [-hcmrq]  [-e  <event>  ]  [-t <seconds> ] [--format <fmt> ] [--timefmt <fmt> ]
       <file> [ ... ]

DESCRIPTION
       inotifywait efficiently waits for changes to files using Linux's inotify(7)  interface.   It
       is suitable for waiting for changes to files from shell scripts.  It can either exit once an
       event occurs, or continually execute and output events as they occur.

OUTPUT
       inotifywait will output diagnostic information on standard error and  event  information  on
       standard output.  The event output can be configured, but by default it consists of lines of
       the following form:

       watched_filename EVENT_NAMES event_filename

       watched_filename
              is the name of the file on which the event occurred.  If the file is a  directory,  a
              trailing slash is output.

       EVENT_NAMES
              are the names of the inotify events which occurred, separated by commas.

       event_filename
              is  output  only when the event occurred on a directory, and in this case the name of
              the file within the directory which caused this event is output.

              By default, any special characters in filenames are not escaped in any way.  This can
              make  the  output  of  inotifywait difficult to parse in awk scripts or similar.  The
              --csv and --format options will be helpful in this case.

OPTIONS
       -h, --help
              Output some helpful usage information.

       @<file>
              When watching a directory tree recursively, exclude the  specified  file  from  being
              watched.   The  file  must be specified with a relative or absolute path according to
              whether a relative or absolute path is given for watched directories.  If a  specific
              path is explicitly both included and excluded, it will always be watched.

              Note:  If  you  need  to watch a directory or file whose name starts with @, give the
              absolute path.

       --fromfile <file>
              Read filenames to watch or exclude from a file, one filename per line.  If  filenames
              begin  with  @ they are excluded as described above.  If <file> is `-', filenames are
              read from standard input.  Use this option if you need to watch  too  many  files  to
              pass in as command line arguments.

       -m, --monitor
              Instead of exiting after receiving a single event, execute indefinitely.  The default
              behaviour is to exit after the first event occurs.

       -d, --daemon
              Same as --monitor, except run in the background logging events to a file that must be
              specified by --outfile. Implies --syslog.

       -o, --outfile <file>
              Output events to <file> rather than stdout.

       -s, --syslog
              Output errors to syslog(3) system log module rather than stderr.

       -r, --recursive
              Watch all subdirectories of any directories passed as arguments.  Watches will be set
              up recursively to an unlimited depth.  Symbolic links are not traversed.  Newly  cre‐
              ated subdirectories will also be watched.

              Warning: If you use this option while watching the root directory of a large tree, it
              may take quite a while until all inotify watches are established, and events will not
              be received in this time.  Also, since one inotify watch will be established per sub‐
              directory, it is possible that the maximum amount of inotify watches per user will be
              reached.    The  default  maximum  is  8192;  it  can  be  increased  by  writing  to
              /proc/sys/fs/inotify/max_user_watches.

       -q, --quiet
              If specified once, the program will be less verbose.  Specifically, it will not state
              when it has completed establishing all inotify watches.

              If  specified  twice,  the  program will output nothing at all, except in the case of
              fatal errors.

       --exclude <pattern>
              Do not process any events whose filename matches the specified POSIX extended regular
              expression, case sensitive.

       --excludei <pattern>
              Do not process any events whose filename matches the specified POSIX extended regular
              expression, case insensitive.

       -t <seconds>, --timeout <seconds>
              Exit if an appropriate event has not occurred within <seconds> seconds. If  <seconds>
              is a negative value (the default), wait indefinitely for an event.

       -e <event>, --event <event>
              Listen  for  specific event(s) only.  The events which can be listened for are listed
              in the EVENTS section.  This option can be specified more than once.  If omitted, all
              events are listened for.

       -c, --csv
              Output  in  CSV  (comma-separated  values) format.  This is useful when filenames may
              contain spaces, since in this case it is not safe to simply split the output at  each
              space character.

       --timefmt <fmt>
              Set  a time format string as accepted by strftime(3) for use with the `%T' conversion
              in the --format option.

       --format <fmt>
              Output in a user-specified format, using printf-like syntax.  The event strings  out‐
              put  are limited to around 4000 characters and will be truncated to this length.  The
              following conversions are supported:

       %w     This will be replaced with the name of the Watched file on which an event occurred.

       %f     When an event occurs within a directory, this will be replaced with the name  of  the
              File which caused the event to occur.  Otherwise, this will be replaced with an empty
              string.

       %e     Replaced with the Event(s) which occurred, comma-separated.

       %Xe    Replaced with the Event(s) which occurred, separated by whichever character is in the
              place of `X'.

       %T     Replaced with the current Time in the format specified by the --timefmt option, which
              should be a format string suitable for passing to strftime(3).

EXIT STATUS
       0      The program executed successfully, and an event occurred  which  was  being  listened
              for.

       1      An  error  occurred  in  execution of the program, or an event occurred which was not
              being listened for.  The latter generally occurs if something happens which  forcibly
              removes  the  inotify  watch,  such as a watched file being deleted or the filesystem
              containing a watched file being unmounted.

       2      The -t option was used and an event did not occur in the specified interval of time.
      0  -  收到了指定的事件
      1  -  收到了没有指定的事件，或者出现了一些错误
      2  -  没有收到事件

EVENTS
       The following events are valid for use with the -e option:

       access A watched file or a file within a watched directory was read from.

       modify A watched file or a file within a watched directory was written to.

       attrib The metadata of a watched file or a file within a  watched  directory  was  modified.
              This includes timestamps, file permissions, extended attributes etc.

       close_write
              A watched file or a file within a watched directory was closed, after being opened in
              writeable mode.  This does not necessarily imply the file was written to.

       close_nowrite
              A watched file or a file within a watched directory was closed, after being opened in
              read-only mode.

       close  A  watched file or a file within a watched directory was closed, regardless of how it
              was opened.  Note that this is actually implemented  simply  by  listening  for  both
              close_write  and close_nowrite, hence all close events received will be output as one
              of these, not CLOSE.

       open   A watched file or a file within a watched directory was opened.

       moved_to
              A file or directory was moved into a watched directory.  This event  occurs  even  if
              the file is simply moved from and to the same directory.

       moved_from
              A  file  or  directory was moved from a watched directory.  This event occurs even if
              the file is simply moved from and to the same directory.

       move   A file or directory was moved from or to a watched  directory.   Note  that  this  is
              actually  implemented simply by listening for both moved_to and moved_from, hence all
              move events received will be output as one or both of these, not MOVE.

       move_self
              A watched file or directory was moved. After this event, the file or directory is  no
              longer being watched.

       create A file or directory was created within a watched directory.

       delete A file or directory within a watched directory was deleted.

       delete_self
              A  watched  file or directory was deleted.  After this event the file or directory is
              no longer being watched.  Note that this event can occur even if it is not explicitly
              being listened for.

       unmount
              The  filesystem  on  which  a watched file or directory resides was unmounted.  After
              this event the file or directory is no longer being watched.  Note  that  this  event
              can occur even if it is not explicitly being listened to.

EXAMPLES
   Example 1
       Running  inotifywait  at the command-line to wait for any file in the `test' directory to be
       accessed.  After running inotifywait, `cat test/foo' is run in a separate console.

       % inotifywait test
       Setting up watches.
       Watches established.
       test/ ACCESS foo

   Example 2
       A short shell script to efficiently wait for httpd-related log  messages  and  do  something
       appropriate.

       #!/bin/sh
       while ! inotifywait -e modify /var/log/messages; do
         if tail -n1 /var/log/messages | grep httpd; then
           kdialog --msgbox "Apache needs love!"
         fi
       done

   Example 3
       A  custom  output  format  is  used  to  watch  `~/test'.   Meanwhile,  someone  runs `touch
       ~/test/badfile; touch ~/test/goodfile; rm ~/test/badfile' in another console.

       % inotifywait -m -r --format '%:e %f' ~/test
       Setting up watches.  Beware: since -r was given, this may take a while!
       Watches established.
       CREATE badfile
       OPEN badfile
       ATTRIB badfile
       CLOSE_WRITE:CLOSE badfile
       CREATE goodfile
       OPEN goodfile
       ATTRIB goodfile
       CLOSE_WRITE:CLOSE goodfile
       DELETE badfile

BUGS
       There are race conditions in the recursive directory watching code which can cause events to
       be missed if they occur in a directory immediately after that directory is created.  This is
       probably not fixable.

       It is assumed the inotify event queue will never overflow.

AUTHORS
       inotifywait was started by Rohan McGovern, and is currently maintained by  Eric  Curtin  and
       Radu  Voicilas.   https://www.openhub.net/p/inotify-tools/contributors/summary  gives  you a
       more complete list of contributors.

       inotifywait  is  part  of  inotify-tools.   The  inotify-tools  website   is   located   at:
       https://github.com/inotify-tools/inotify-tools/wiki

SEE ALSO
       inotifywatch(1), strftime(3), inotify(7)

inotifywait 3.20.2.2                         2020-02-01                              inotifywait(1)